Armature



Apr. 3, 1923.

J. K. LENCKE .ARMATURE Filed June 2, 1920 E. Y N R 2% M? A w 5 WI A MHW ////fl J, \A m wm Patented Apr. 3, 1923.

UNITED STATES .JOHN K. LENOKE, OF BROOKLYN, NEW YORK.

ARMATURE.

Application filed June 2,

. To all whom it may concern.

Be it known that I, JoI-IN K. LnNonn, a citizen of the United States, residing in Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Armatures, of which the following is a specification.

This invention pertains to an improved armature for a magneto employed to fur nish current for the purpose of igniting the fuel in an internal combustion engine; and it relates particularly to those parts of the armature by which the conductors for carrying the current out of the latter are mounted.

In the use of such magnetos of the high tension type, great trouble is often experienced because of the liability of the armature to sustain damage when it is roughly or unskillfully handled, or subjected to jars and shocks as the automobile or truck carrying the magneto encounters obstructions and inequalities in the roadway. This liability is largely due .to the fact that the armature of a high tension magneto bears a collar of insulation in proximity to parts of the rigid, stationary, framework or housing of the magneto; this collar bearing a movable conductor member or slip ring by which the current is taken to the distributer and thence to the igniters or spark plugs of the engine; and a violent jolt will often cause this collar to crack and break; whereby the generator windings will be grounded and the magneto rendered unserviceable until repaired. The primary object of this invention is to prevent such breakage and I attain my end by a novel construction of insulating collar and the part of the armature immediately associated therewith.

A further object of my invention is to provide a novel design of such an insulating collar adapted to be easily made and to enable the slip ring upon it and the generator windings of the magneto to be quickly and efficiently united.

Other objects and advantages of my invention will appear from the following description, taken with the accompanying drawings, which show one or more preferred forms in which the invention may be embodied. This disclosure, however, is illustrative only, and I may resort to changes as regards shape, size and arrangement of the various members actually shown herein, without departing from the scope and spirit end of the armature 1920. Serial No. 385,977.

of my invention, as the appended claims define the same.

On the drawings Figure 1 is a side view, partly in section, of an armature according to my invention;

Figure 2 is a side elevation of the front appearing in Figure 1;

F gure 3 is a front elevation of said end;

Figures i and 5 are respectively a rear and a side elevation of an insulating collar according to my invention, carried by said armature;

Figure 6 is a view similar to Figure 1, showing the end of a modified armature according to my invention;

Figure 7 is a front elevation of said end; and

Figure 8 is a rear elevation of an insulating collar for such an armature.

The same numerals identify the same parts throughout.

Referring first to Figures 1 to 5 inclusive, I show at 1 an armature for a magneto, this armature being of the well known shuttlewound or H--type, comprising a pair of polepieces 2, connected by a transverse core, not shown, around which are the windings of the generating coils 3. To one end of the polepieces 2 is affixed a head 4 which is hollow and houses a condenser, this head being provided with a solid central shaft or trunnion 5, which ordinarily serves as a drive shaft for the magneto. To the opposite end of the polepieces is secured a head 6, which is also provided with a trunnion 7 This trunion is hollow and on it is mounted an insulating collar 8, carrying an external conductor member or slip-ring 9, to which one of the generating windings 3 is con nected, the other end being grounded In practice the current is led to the slip ring 9 and thence to the distributer and each of the igniters or spark plugs of the engine in succession.

The collar 8 is preferably made in one piece and it is generally cylindrical in outside shape, with end fianges 10, between which the slip ring '9 is situated. Embedded in the collar is a hollow socket-piece 11 which is made of some electrically conductive material and is connected to the ring 9 at one end. The other end of this socketpiece is open; that is, it has a recess or bore extending into same, and this recess or bore one end of the collar in an axial direction.

In this boss'is a passage or open bore 13 which leads to the recess in the socket-piece 11; so that a wire or conductor can be introduced into the boss and forced into contact with the socket-piece, thereby enabling electrical connection between the slip ring 9 and the winding 3 to be easily made. One terminal of the winding 3 is indicated at 14, entering the boss 12; and by reference to Figure 1 it will be seen that when the collar 8 is mounted on the shaft 7, it does not lie directly in contact with the head 6 but is spaced from the head 6 by a gear 15. This gear meshes with the gear (not shown) of the distributing mechanism of the magneto; and both the gear 15 and the head 6 will be provided with alined openings to enable the boss 12 to pass therethrough into proximity to the winding 3, and the wire let will therefore enter the boss 12 at a point on the inside of the armature 1, that is, to the rear of this head 6.

-The collar 8 is provided with a bore 16 extending axially therethrough from one end to the other to enable the shaft 7 to be slipped through the collar when the collar is mounted on the shaft; and the collar 8 must be of sufficient thickness between this bore and the ring 9. As above pointed out, the boss must be in line with the socket-piece 11, or, in other words, the boss must be in such position that connection between the ring 9 and the winding 3 can be made by passing the leadwire 14: in through the boss 12 to the socket-piece 11. To enable this connection to be conveniently and easily effected, the passage'13 and the recess in the socket-piece 11 must be as straight and as alined as possible; and for this reason of course, the axis of the boss 12' must lie Within the inner face of the ring 9. At the same time this boss 12 must be of sufficient thickness to give it the required strength to resist breakage, but this thickness is limited on the one hand by the fact that it must be located to project from one end of the collar at a point between the bore 16 and the outside surface of the collar between the flanges 10; and on the other hand, by the fact that it cannot, except to a certain extent, occupy any of the space provided by the bore 16 to accommodate the shaft 7. The size and location of the boss 12 must therefore be a compromise between these factors. I dispose this boss in the proper position and at the same time make it thick enough to give it the required strength by so designing the inside of the bore 16 that the boss will be nearer along one side to the central axis of the bore 16 thanthe major portion or per tions of the inside surface of the bore 16.

Preferably thisbore 16 is cylindrical for the rio-r surface of the bore 16 in the form of a plane section 18, which intersects the cylindrical portion 17, providing in effect, a flat, adjacent the middle of which the boss 12 unites with the body of the collar 8. That is, the boss 12 is flush along one side with the plane portion 18. I can thus make the boss 12 thick and strong enough and near enough to the axis of the bore 16 to have its passage 13 in line with the recess in the socket-piece 11, and at the same time leave space enough at the center of the collar to receive the shaft 7. This shaft is likewise generally cylindrical, but a part of its outside cylindrical surface is removed or cut away to provide a flat section 19; which will coincide with the plane section 18 when the collar 8 and head 6 are assembled. The shaft 7 will thus conform to the inside shape of the bore 16 and will make a snug fit with the collar; and as the armature rotates, the collar will revolve with it.

In Figures 6 to 8 inclusive, I show a collar 8 having a bore 16 that is generally cylindrical but provided with a reentrant convex portion 20, instead of a plane section 18; and the shaft 7 has a reentrant concave portion 21 to receive the convex portion 20 when the shaft is slipped through the bore 16. By this construction the boss 12, flush along one side with the portion 20, can be placed a little closer to the axis of the collar than in the first eight figures.

The opening in the gear 15 for the boss 12 is indicated at 22 and the corresponding opening in the head 6 by the numeral 23. The heads 4 and 6 are provided with holes 24:, shown in the head 6 only in Figures 3 and 7 to receive insulated bolts which unite them to the polepieces 2; and the front head 6 may have other holes 26'for screws toenable the gear 15 to be fastened in place. These holes and screws may sometimes be omitted. V

The shaft 7 is made hollow with a bore or passage 27, and is provided adjacent its outer end with a shoulder 28. In practice the timer mechanism will be secured to the outer end of this shaft and united to the low tension winding on the armature by an insulated connection which extends inward through the bore 27; the high tension winding being joined to the ring 9. In practice the portion of the armature between the outer end of the shaft 7 and the shoulder 28 will engage a suitable anti-friction bearing; and a dished resilient plate or washer will he slipped over the outer end of the shaft 7 and made to engage'the shoulder 28 around its center, while the circumference of this washer will press upon the adjacent end of the collar'8 and hold it firmly against the gear 15.

By the above construction the collar 8 insulates the ring 9 as sufliciently as required;

and the boss 12 can be made of sufficient strength to resist damage when the magneto can be assembled, involves relatively little' expense and can be easily and quickly accomplished.

One must understand that the plane portion 18, likewise the convex portion 20, are not to be regarded as keys for engaging the shaft 7 so as to make the collar 8 turn with the shaft 7. In practice the bore 16 is made large enough to fit upon the shaft 7 loosely, in order to permit the shaft, which is of metal, to expand in the bore 16 of the collar 8, which is of insulation, such as rubber, without any risk of bursting or cracking the collar; and the collar is made to revolve with the shaft by reason of the fact that the boss 12 projects through the gear 15, which is rigid with the shaft 7, and the head 6. The object. in providing the plane portion 18 and the convex portion 20 is to permit the axis of the boss 12 to be located relatively close to the axis of the bore 16 and further'to make the boss 12 a little thicker on the side presented to the bore 16, so as to strengthen it, and make it better adapted to resist shearing off or breaking; and at the same time avoid interfering with the shaft 7. If the bore 16 were cut out to make it entirely cylindrical and remove the portion 18 or the portion 20 entirely, the boss 12 would have either to be cut away to some extent on its outside surface; or moved farther away from the axis of the bore 16 if cutting away the boss is not. to be allowed. To move the boss 12 farther outward away from the axis of the collar 8 would necessitate making this collar bigger and entail an increase in the size of the magneto; while to cut away a part of the outside of the boss 12 on the side presented to the bore 16 would reduce its cross-sectionv and greatly weaken it. lVith a weak boss damage can easily occur and I have known of numerous magnetos which were failures and had to be returned to the factory after being put into use because the boss 12 had been cut away in the manner specified. To move the boss 12 a little farther in towards the axis of the bore 16 and provide the plane portion 18 or the convex portion 21, so as to avoid cutting away the boss on its outside surface, and at the same time avoid filling the bore 16 too much, so as not to interfere with the shaft 7, and thus obviate the need for making the collar any larger, offers a practical solution for a very serious difiiculty that the manufacturer of magnetos 'has heretofore been obliged to contend with; namely, the strengthening of the boss 12, without interfering with the space required by the shaft 7 or requiring any increase in the size of the collar 8; and by strengthening the boss in such a manner the breaking or shearing off of this boss and the failure of the magneto are effectually prevented.

The wire 14 may of course be soldered or plugged after its end is inserted into the piece 11.

Having described my invention, What I believe to be new and. desire to secure and patent by Letters Patent of the United States, is:

1. An insulating collar to carry a con ductor member on its exterior, said collar having a central bore therethrough extending from end to end and having a boss proj ecting from one end of the collar, said boss being closer along one side to the axis of said bore than the major portion of the inside surface of said bore.

2. An insulating collar to carry a conductor member on its exterior, said collar having a central bore therethrough extending from end to end and having a boss projecting from one end of the collar, the internal surface of said bore being for the most part cylindrical, said boss being closer along one side to the axis of said bore than the major portion of the inside surface of said bore.

3. An insulating collar to carry a conductor member, said collar having a bore extending therethrough from end to end, the interior surface of said bore being cylindrical for the most part, but comprising a plane portion intersect-ing the cylindrical portion, and a boss projecting from one end of the collar and being flush along one side with said plane portion.

1. An insulating collar carrying an exterior conductor member and having a bore extending therethrough from end to end, a boss projecting from one end of said collar and being closer along one side to the axis of the bore than portions of the interior surface of the bore, and a head for mounting said collar, said head having a shaft projecting through said bore and conforming to the interior shape of the same. 5. An insulating collar carrying an external conductor member and having a bore extending from end to end therethrough, the interior surface of said bore being for the most part cylindrical, a boss projecting axially from one end of the collar and being closer on one side to the axis of the bore than said cylindrical surface, and a head to carry said collar, said head having a shaft projecting through the bore and conforming to the interior shape thereof.

6. The combination of a collar having an external conductor and having a bore there- .through from end to end,the inside surface of said bore being cylindrical for the most part, but including a plane portion, a boss projecting axially from one end of the collar and being substantially flush along one side with said plane portion, and a head having'a shaft projecting therefrom to pass through the bore of the collar and carry the collar, said shaft being cylindrical With a flat section to make a snug fit with the bore in said collar. I

7. The combination of an insulating collar, a conductor member carried by the collar, a boss projecting from one end of the theboss being closer along one side to the axis of said bore than the greater portion of the inside surface of said bore.

In Witness whereof I have signed my name to this specification this 31st day of March, 1920. f

JOHN K. LENCKE. 

